• 제목/요약/키워드: Correcting System

검색결과 410건 처리시간 0.033초

전시 공간에서 지능형 개인화 서비스를 위한 스마트 폰 어플리케이션 설계 (The Design of Smart-phone Application Design for Intelligent Personalized Service in Exhibition Space)

  • 조영희;최이권
    • 지능정보연구
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    • 제17권2호
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    • pp.109-117
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    • 2011
  • 전시 공간에서 전시 제공자는 자신의 마케팅 정보를 원활하게 제공하고 관람객의 반응을 실시간으로 확인하기를 원한다. 또한 전시 관람객은 자신이 가장 관심 있어 하는 분야의 부스를 관람하고 그 분야에 대한 정보를 얻고 싶어한다. 그런데 전시장을 방문하는 관람객들에게 상호 작용적 맞춤 개인화 마케팅 서비스를 관람객의 단말기를 통해 제공하게 된다면 전시 제공자와 관람객 모두의 요구를 충족하게 될 것이다. 이러한 서비스를 제공하기 위해서는 사용자의 의도를 인지할 수 있어야 하고 그 인지된 정보를 기준으로 해서 선별적인 서비스를 제공해야 한다. 본 논문에서는 전시 공간에서 관람객 개개인의 선호도와 상황을 인식하고 인식된 정보를 기본으로 해서 관람객 개인별로 가장 적합한 전시 참가 업체의 마케팅 정보나 부스 정보를 관람객이 소유한 스마트폰을 통해 제공하는 지능형 개인화 서비스 어플리케이션을 설계하였다.

인성교육 이해방식과 방법론에 관한 일고찰 - 인간 본성과 감정의 올바른 이해를 토대로 한 인성교육으로의 전환 - (A Study on the Understanding Method and Methodology of Character Education: A Transition to Character Education based on a Correct Understanding and Attitude towards Human Nature and Emotions)

  • 김성실
    • 대순사상논총
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    • 제42집
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    • pp.201-226
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    • 2022
  • 인성교육은 먼저 인성에 대한 명확한 정의로부터 시작된다. 인성이 인간의 본성 혹은 성격이라는 주장들이 있으나 교육적 측면으로 이해한다면 인성은 곧 선하냐 악하냐에 대한 문제로 귀결된다. 인간의 본성으로 보나 성격으로 보나 결국 교육이라는 의미에서 인간의 본성이 악하다는 입장에서의 교육과 인간의 본성이 선하다는 입장에서의 교육은 상당한 차이가 난다. 오늘날 현대교육은 인간의 본성이 악하다는 입장에서 교육은 미성숙한 자를 성숙한 상태로 이끄는 것으로 보고 있다. 하지만 인간의 본성이 악하다면 한번도 선하게 된적도 없는 우리의 본성을 무슨 수로 선하게 만드는 교육을 시행할 수 있을 것인가. 인성교육이 단순히 잘못된 사례를 중심으로 고쳐나가는 방식의 에티켓 교육이나 주입식 예의범절 교육이 된다면 그 이전에 잘못된 교육사례의 답습밖에 안될 것이다. 그런 의미의 인성교육은 교육이 아니라 교정이다. 교육은 인간의 미성숙하기에 끊임없이 교정·교화해나가는 절차가 아니라 완전한 나를 깨닫고 이해하는 방식이어야 한다. 그런 의미에서 본고에서는 인성교육에서 말하는 인간의 본성이 선하다는 입장 하에서 인간의 선한 본성으로 드러난 감정을 중심으로 감정의 자기이해가 올바른 인성교육임을 말하고자 하였다. 인성은 교육 가능하지만 이때의 교육은 결코 없던 인성을 채워넣는 방식이 아닌 이미 완전하고 선한 나의 본성을 이끌어내는 방식이어야 한다. 어떤 행동을 '하지마'라는 부정적 명령보다 '왜 하면 안될지'에 대해 생각하는 것, 그리고 그 이전에 내 감정이 그렇게 느끼고 말해주는 것에 귀 기울여 듣는 '감정의 자기이해'가 녹아들어가는 인성교육이 된다면 가장 바람직한 교육이 될 것이다.

중국의 사지서목에 대하여 -육사예문$\cdot$경적지의 분류 및 편목체재 비교를 중심으로- (On the Bibliographies of Chinese Historical Books - Classifying and cataloguing system of six historical bibliographies -)

  • 강순애
    • 한국문헌정보학회지
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    • 제24권
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    • pp.289-332
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    • 1993
  • In china, six bibliographies of offical historical books are evaluated at the most important things among the systematically-editing bibliographies. These bibliographies would be usful to study the orign of classical sciences and their development, bibliographic research of Chinese classics, bibliographic judgement on genuine books, titles, authors, volumes. They could be refered to research into graving, correcting, and existence of ancient books. therefore, these bibliographies would be applied to estimation the phase of scientific and cultural development. The study of these bibliographies has been not yet made in Korea. This thesis lays its importance on the background of their appearance, their classification norms, organizing system of their catalogue, and comparison between their difference. 1. Editing and compiling of Chilyak (칠약) by Liu Chin (유흠) and official histories played an important role of entering an apperance of historical book's bibliographies. Chilyak has been lost. However, its classification and compiling system of classical books would be traced by Hansoyemunji(한서예문지) of which basic system is similar to Chilyak. It classified books according to their scientific characteristic. If a few books didn't have their own categories, they were combined by the circles parallel to the books' characteristic. With the books classified under the same scientific characteristic, they were again divided into the scientific schools or structures. It also arranged the same kinds of books according to the chronology. The some books wi th duplicate subjects were classified multiplely by their duplicate subject. 2. Ssu-ma Chon's (사마천) The Historical Records (Saki, 사기) and Pan Ku's (반고) The History of the Former Han Dynasty (Hanso, 한서) has also took effects on appearance of historical books' bibliographies. Covering overall history, Saki was structured by the five parts: The basic annals(본기), the chronological tables (표), the documents (서), the hereditary houses (세가), biographies (열전). The basic annals dealt with kings and courts' affairs according to the chronology. The chronological tables was the records of the annals. The documents described overall the social and cultural systems. The hereditary houses recorded courts' meritorious officials and public figures. The biographies showed exemplars of seventy peoples selected by their social status. Pan Ku(반구)'s The History of the Former Han Dynasty(한서) deserved to be called the prototype for the offical histories after Saki's (사기; The Historical Records) apperance. Although it modelled on Saki, it had set up its own cataloguing system. It was organized by four parts; the basic annals (본기), the chronological tables (표), treatises(지), biographies (열전). The documents in the Hanso(한서) was converted into treatises(지). The hereditary houses and biographies were merged. For the first time, the treatise with The Yemunji could operate function for historical bibliographies. 3. There were six historical bibliographies: Hansoyemunji(한서예문지), Susokyongjeokji (수서경적지), Kudangsokyongjeokji(구당서경적지), Shindangsoyemunji (신당서예문지), Songsayemunji (송사예문지), Myongsayemunji (명사예문지). 1) Modelling on Liu Chin's Chilyak except Chipryak(집략), Hansoyemunji divided the characteristic of the books and documents into six parts: Yukrye(육예), Cheja(제자), Shibu(시부), Pyongsoh(병서), Susul(수술), Pangki(방기). Under six parts, there were thirty eight orders in Hansoyemunji. To its own classification, Hansoyemunji applied the Chilyak's theory of classification that the books or documents were managed according to characteristic of sciences, the difference of schools, the organization of sentences. However the overlapped subjects were deleted and unified into one. The books included into an unsuitable subject were corrected and converted into another. The Hansoyemunji consisted of main preface (Taesoh 대서), minor preface (Sosoh 소서) , the general preface (Chongso 총서). It also recorded the introduction of books and documents, the origin of sciences, the outline of subjects, and the establishment of orders. The books classified by the subject had title, author, and volumes. They were rearranged by titles and the chronological publication year. Sometimes author was the first access point to catalogue the books. If it was necessary for the books to take footnotes, detail notes were formed. The Volume number written consecutively to order and subject could clarify the quantity of books. 2) Refering to Classfication System by Seven Norms (칠분법) and Classification System by Four Norms(사분법), Susokyongjeokji(수서경적지) had accomplished the classification by four norms. In fact, its classification largely imitated Wanhyosoh(완효서)'s Chilrok(칠록), Susokyongjeokji's system of classification consisted of four parts-Kyung(경), Sa(사), Cha(자), Chip(칩). The four parts were divided into 40 orders. Its appendix was again divided into two parts, Buddihism and Taiosm. Under the two parts there were fifteen orders. Totally Susokyongjeokji was made of six parts and fifty five orders. In comparison with Hansoyemunji(한서예문지), it clearly showed the conception of Kyung, Sa, Cha, Chip. Especially it deserved to be paid attention that Hansoyemunji laied history off Chunchu(춘추) and removed history to Sabu(사부). However Chabu(사부) put many contrary subjects such as Cheja(제자), Kiye(기예), Sulsu(술수), Sosol(소설) into the same boundary, which committed errors insufficient theoretical basis. Anothor demerit of Susokyongjeokji was that it dealt with Taiosm scriptures and Buddism scriptures at the appendix because they were considered as quasi-religion. Its compilation of bibliographical facts consisted of main preface(Taesoh 대서), minor preface(Sosoh 소서), general preface (Chongsoh 총서), postscript (Husoh 후서). Its bibliological facts mainly focused on the titles. Its recorded authors' birth date and their position. It wrote the lost and existence of books consecutive to total number of books, which revealed total of the lost books in Su Dynasty. 3) Modelling on the basis of Kokumsorok(고분서록) and Naewaekyongrok(내외경록), Kudangsokyongjeokji(구당서경적지) had four parts and fourty five orders. It was estimated as the important role of establishing basic frame of classification by four norms in classification theory's history. However it had also its own limit. Editing and compling orders of Kudangsokyongjeokji had been not progressively changed. Its orders imitated by and large Susokyongjeokji. In Its system of organizing catalogue, with its minor preface and general preface deleting, Kudangsokyongjeokji by titles after orders sometimes broke out confusion because of unclear boundaries between orders. 4) Shindangsoyemunji(신당서예문지), adding 28,469 books to Kudangsokyongjeokji, recorded 82,384 books which were divided by four parts and fourty four orders. In comparison with Kudangkyongjeokj, Sindangsoyemunji corrected unclear order's norm. It merged the analogical norms four orders (for instance, Kohun 고훈 and Sohakryu 소학류) and seperated the different norms four orders (for example, Hyokyong 효경 and Noneuhryu 논어류, Chamwi 참위 and Kyonghaeryu 경해류, Pyonryon 편년 and Wisaryu 위사류). Recording kings' behaviors and speeches (Kikochuryu 기거주류) in the historical parts induced the concept of specfication category. For the first time, part of Chipbu (집부) set up the order of classification norm for historical and literatural books and documents (Munsaryu 문사류). Its editing and compiling had been more simplified than Kudangsokyongjeokji. Introduction was written at first part of bibliographies. Appendants except bibliographic items such subject, author, title, volume number, total were omitted. 5) Songsayemunji(송사예문지) were edited in the basis of combining Puksong(북송) and Namsong(남송), depending on Sabukuksayemunji(사부국사예문지). Generally Songsayemunji had lost a lot of bibliographical facts of many books. They were duplicated and wrongly classified books because it committed an error of the incorrectly annalistic editing. Particularly Namsong showed more open these defaults. Songsayemunji didin't include the books published since the king Youngchong(영종). Its system of classification was more better controlled. Chamwiryu(참위류) in the part of Kyongbu(경부) was omitted. In the part of history(Sabu 사부), recordings of kings' behaviors and speeches more merged in the annals. Historical abstract documents (Sachoryu 사초류) were seperately arranged. In the part of Chabu(자부), Myongdangkyongmaekryu(명당경맥류) and Euisulryu(의술류) were combined. Ohangryu(오행류) were laied off Shikuryu(시구류). In the part of Chipbu(집부), historical and literatural books (Munsaryu 문사류) were independentely arranged. There were the renamed orders; from Wisa(위사) to Paesa(패사), Chapsa (잡사) to Pyolsa(열사), Chapchonki(잡전기) to Chonki(전기), Ryusoh(류서) to Ryusa(류서). Introduction had only main preface. The books of each subject catalogued by title, the volume number, and author and arranged mainly by authors. Annotations were written consecutively after title and the volume number. In the afternote the number of not-treated books were revealed. Difference from Singdangsohyemunji(신당서예문지) were that the concept and boundary of orders became more clearer. It also wrote the number of books consecutive to main subject. 6) Modelling on Chonkyongdangsomok (경당서목), Myongsayemunji(명사예문지) was compiled in the basis of books and documents published in the Ming Danasty. In classification system, Myongsayemunji partly merged and the seperated some orders for it. It also deleted and renamed some of orders. In case of necessity, combining of orders' norm was occured particulary in the part of Sabu(사부) and Chabu(자부). Therefore these merging of orders norm didn't offer sufficient theretical background. For example, such demerits were seen in the case that historical books edited by annals were combined with offical historical ones which were differently compiled and edited from the former. In the part of Chabu(자부), it broke out another confusion that Pubga(법가), Meongga(명가), Mukga(묵가), Chonghweongka's(종횡가) thoughts were classified in the Chapka(잡가). Scriptures of Taiosim and Buddhism were seperated from each other. There were some deleted books such as Mokrokryu(목록류), Paesaryu(패사류) in the part of history (Sabu 사부) and Chosaryu(초사류) in the part of Chipbu(집부). The some in the each orders had been renamed. Imitating compiling system of Songsayemunji(송사예문지), with reffering to its differ-ence, Myongsayemunji(명사예문지) wrote the review and the change of the books by author. The number of not-treated books didn't appear at the total. It also deleted the total following main subject.

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치과 파노라마 촬영에서 환자의 피폭선량에 관한 연구 (A Study on the Patient Exposure Doses from the Panoramic Radiography using Dentistry)

  • 박일우;정원교;황형석;임성환;이대남;임인철;이재승;박형후;곽병준;유윤식
    • 한국방사선학회논문지
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    • 제7권1호
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    • pp.17-24
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    • 2013
  • 본 연구는 파노라마 표준 촬영에서 환자의 피폭 선량을 측정하여 방사선 생물학적 위험인자를 평가하고 환자의 피폭 선량 저감화 방안을 제시하고자 하였다. 피폭 선량의 측정 오차를 최소화하기 위하여 각 OSL 선량계의 교정상수를 구하였으며 파노라마 표준 촬영에서 간접적으로 포함되는 좌 우측 수정체와 갑상선, 직접적으로 포함되는 상 하 입술, 하악골 첨부, 촬영 중심점을 대상으로 ICRP에서 권고하는 인체 모형 표준 팬텀을 이용하여 측정하였다. 측정 결과, 촬영 중심점의 선량이 $413.67{\pm}6.53{\mu}Gy$로 최대였으며 상 하 입술의 경우 각각 $217.80{\pm}2.98{\mu}Gy$, $215.33{\pm}2.61{\mu}Gy$이었다. 또한 파노라마 표준 촬영에서 간접적으로 포함되는 좌 우측 수정체의 등가선량은 각각 $30.73{\pm}2.34{\mu}Gy$, $31.87{\pm}2.50{\mu}Gy$이었으며 하악골 첨부 및 갑상선의 등가선량은 $276.73{\pm}14.43{\mu}Gy$, $162.07{\pm}4.13{\mu}Gy$이었다. 결론적으로 측정된 피폭 선량은 방사선 생물학적 효과를 유발할 수 있었으며 치과 의료기관의 파노라마 표준 촬영에서 환자의 피폭 선량에 대한 저감화 방안으로 국제기구에서 권고하고 있는 방사선 방어 원칙에 대한 정당한 해석과 제도적 뒷받침(regulation)이 필요하다. 이에 파노라마 검사에 의한 피폭 선량은 기술적 경제적 측면뿐 만 아니라 사회적 인자를 고려하여 합리적으로 용인 가능한 수준까지 최소화하기 위한 체계화된 프로토콜의 제정과 주변 결정 장기를 방어하기 위한 방사선 보호 기구에 대한 추가적 연구가 필요할 것으로 판단되었다.

산업은행: 금융 IT 아웃소싱 - 공동협력으로 안전한 문을 연다 (A Case Study - IT Outsourcing of the Korea Development Bank)

  • 강주영;이재규
    • 경영정보학연구
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    • 제7권2호
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    • pp.229-255
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    • 2005
  • 산업은행은 1999년 제1금융권으로는 최초로 IT 운영에 대한 전체 아웃소싱을 추진하였다. 대부분의 은행들이 금융사고와 보안, 그리고 파업에 대한 위험 등을 이유로 타회사 방식 아웃소싱을 꺼리는 상황에서 산업은행의 이러한 시도는 많은 주목을 받았다. 이후 산업은행은 끊임없이 아웃소싱의 문제점들을 진단하고 이를 개선하기 위하여 다양한 보완책을 강구하였다. 이러한 개선의 결과로, 산업은행의 IT 아웃소싱은 외주 운영기와 공동 운영기를 지나 금융권 IT 아웃소싱 최초로 타 은행에 비해 선구적인 아웃소싱 방식인 책임운영 체제를 갖추게 되었다. 책임운영을 통해 산업은행은 최신의 향상된 IT 수준을 얻고 내부 인력을 핵심역량에 집중시키며 부족 인력의 즉시 수급이 가능하게 되어 유연성을 확보할 수 있었다. 또한, 외주업체와의 관계를 공급자와 수요자의 일방적 관계로 설정하지 않고 함께 책임지는 책임 운영 방식 체제로 전환함으로써 자체 보유역량과 IT 전문업체의 노하우를 통합할 수 있게 되어 IT 아웃소싱의 순기능을 활용할 수 있게 되었다. 이와 같은 산업은행의 IT 아웃소싱 사례를 살펴봄으로써 일반적으로 타 회사 방식 아웃소싱에 대해 갖고 있는 우려가 현실적인 것인지, 혹은 극복될 수 있는 것인지를 확인하고, 자회사 방식의 아웃소싱에 비해 어떤 장점들을 갖고 있으며 어떤 성과를 보이고 있는지 정리하였다. 뿐만 아니라, 타 회사방식 아웃소싱에 대한 잘못된 견해들을 바로잡음으로써 폐쇄된 금융 IT 아웃소싱 시장의 구조를 개선하고 국내 IT 아웃소싱 업체의 국제 경쟁력을 제고할 수 있을 것으로 기대한다.

혼합 최저고도각 반사도 자료를 이용한 레이더 강우추정 정확도 향상 (Improvement of Radar Rainfall Estimation Using Radar Reflectivity Data from the Hybrid Lowest Elevation Angles)

  • 류근수;정성화;남경엽;권수현;이청룡;이규원
    • 한국지구과학회지
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    • 제36권1호
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    • pp.109-124
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    • 2015
  • 레이더 반사도를 이용한 강수추정의 개선을 위해 새로운 접근 방식인 경북대학교에서 개발한 하이브리드 고도면을 이용한 강수량 추정기법(Hybrid Surface Rainfall, KNU-HSR)을 사용하였다. KNU-HSR기법은 지형에코와 레이더 빔차폐의 영향을 받지 않는 2차원 하이브리드 고도면에서의 반사도를 이용하여 강수량을 추정한다. 본 연구에서는 정적 HSR 및 동적 HSR기법이 사용되었으며 비교 검증되었다. 정적 HSR은 빔차폐지도와 지형에코지도를 사용하며, 동적 HSR은 정적 HSR에 추가적으로 실시간 퍼지로직 품질관리를 통한 품질지수지도를 사용한다. 검증을 위해 상관계수(correlation coefficient), 총비율(total ratio), 평균편의(mean bias), 정규화된 표준편차(normalized standard deviation), 평균 상대오차(mean relative error)를 사용하였으며, 10개 강우사례의 지상우량계 강우자료를 이용하여 두 HSR의 강우추정 성능을 평가하였다. 모든 검증지수에서 동적 HSR은 반사도 보정을 하지 않은 정적 HSR에 비해 더 우수한 성능을 보였다. 동적 HSR은 레이더로부터 근거리에서는 과대추정하였으며 원거리에서는 빔 폭 확장 및 빔 고도증가로 인해 과소추정하였다. 동적 HSR의 정규화된 표준편차와 평균상대오차는 레이더로부터의 거리에 관계없이 가장 좋은 결과를 보였다. 정적 HSR은 약한 강우강도에서 상당히 과대추정하였으나 동적 HSR은 모든 강우강도에서 1.0에 총비율을 보였다. 반사도의 시스템오차 보정 후, 동적 HSR의 정규화된 표준편차와 평균상대오차는 각각 약 20%와 15%로 개선되었다.

정상인에서 혈중 연과 zinc protoporphyrin과의 상관관계 및 HPLC 와 Hematofluorometer로 측정한 zinc protoporphyrin량간의 비교 (The Relationship between Zinc protoporphyrin and Lead levels in Normal Adults' Blood And Comparison of Zinc protoporphyrin values by High Performance Liquid Chromatograph and Hematofluorometer)

  • 김강윤;김현욱
    • 한국산업보건학회지
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    • 제3권2호
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    • pp.141-151
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    • 1993
  • Blood samples obtained from 200 adults who had visited the "S" general hospital were analyzed to compare the zinc protoporphyrin (ZPP) levels quantified by high performance liquid chromatograph (HPLC) and by hematofluorometer (HF) to investigate the methodological difference if any and the relationship between the levels of blood lead and ZPP among no-lead exposed adults. Also investigated were the distribution of ZPP and protoporphyrin IX (PPIX) concentrations, the establishment of normal levels of blood ZPP and blood lead, and the contribution of age and sex factors to these values. These subjects had no previous occupational exposure to lead. The results obtained were as follows : 1. The mean values of blood lead for male and female subjects were $9.46{\pm}2.44{\mu}g/dl$ and $8.09{\pm}2.17{\mu}g/dl$, respectively. The difference observed in the mean concentrations between male and female subjects was statistically very significant. 2. The mean values of blood ZPP by HPLC for male and female subjects were $15.94{\pm}4.55{\mu}g/dl$ and $22.26{\pm}6.61{\mu}g/dl$, respectively. The difference observed in the mean concentrations between male and female subjects was statistically not significant. The mean values of blood PPIX by HPLC for male and female subjects were $2.51{\pm}1.78{\mu}g/dl$ and $2.81{\pm}1.56{\mu}g/dl$, respectively. The difference observed in the mean concentrations between male and female subjects was statistically not significant. 3. The mean values of blood ZPP by HF for male and female subjects were $28.44{\pm}7.11{\mu}g/dl$ and $37.77{\pm}8.04{\mu}g/dl$, respectively. The difference observed in the mean concentrations between male and female subjects was statistically very significant. 4. No statistically significant correlation was found between the levels of blood ZPP and blood lead. 5. The ratio of ZPP and protoporphyrin IX (PPIX) concentration to erythrocyte protoporphyrin (EP, EP=ZPP+PPIX) concentration was 87.4% and 12.6%, respectively. 6. A statistically very significant correlation was found between the ZPP concentrations determined by HPLC and the values by HF (r=0.7565). The ZPP concentraitons quantified by HF were 1.75 times as high as the values obtained by HPLC. 7. The blood ZPP concentrations quantified by HPLC, HF, and spectrofluorometer (SF) from the blood samples obtained from 14 lead-exposed workers and from 16 no-lead exposed adults showed wide variations. The ZPP concentrations by HF were the highest followed by the levels obtained by SF and by HPLC. In the exposed group, no statistically significant difference was found among three methods of quantifying blood ZPP levels. In the no-lead exposed group, however, statistically significant difference was observed among these methods. The ZPP concentrations by HF were about twice as high as those of by HPLC or by SF. Among three methods of quantifying blood ZPP (HPLC, SF and HF), the results revealed significant difference. Therefore it is suggested that objective methods of quantifying blood ZPP and a system of correcting different ZPP levels be developed by the ministry of Labor.

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다양한 다분류 SVM을 적용한 기업채권평가 (Corporate Bond Rating Using Various Multiclass Support Vector Machines)

  • 안현철;김경재
    • Asia pacific journal of information systems
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    • 제19권2호
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    • pp.157-178
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    • 2009
  • Corporate credit rating is a very important factor in the market for corporate debt. Information concerning corporate operations is often disseminated to market participants through the changes in credit ratings that are published by professional rating agencies, such as Standard and Poor's (S&P) and Moody's Investor Service. Since these agencies generally require a large fee for the service, and the periodically provided ratings sometimes do not reflect the default risk of the company at the time, it may be advantageous for bond-market participants to be able to classify credit ratings before the agencies actually publish them. As a result, it is very important for companies (especially, financial companies) to develop a proper model of credit rating. From a technical perspective, the credit rating constitutes a typical, multiclass, classification problem because rating agencies generally have ten or more categories of ratings. For example, S&P's ratings range from AAA for the highest-quality bonds to D for the lowest-quality bonds. The professional rating agencies emphasize the importance of analysts' subjective judgments in the determination of credit ratings. However, in practice, a mathematical model that uses the financial variables of companies plays an important role in determining credit ratings, since it is convenient to apply and cost efficient. These financial variables include the ratios that represent a company's leverage status, liquidity status, and profitability status. Several statistical and artificial intelligence (AI) techniques have been applied as tools for predicting credit ratings. Among them, artificial neural networks are most prevalent in the area of finance because of their broad applicability to many business problems and their preeminent ability to adapt. However, artificial neural networks also have many defects, including the difficulty in determining the values of the control parameters and the number of processing elements in the layer as well as the risk of over-fitting. Of late, because of their robustness and high accuracy, support vector machines (SVMs) have become popular as a solution for problems with generating accurate prediction. An SVM's solution may be globally optimal because SVMs seek to minimize structural risk. On the other hand, artificial neural network models may tend to find locally optimal solutions because they seek to minimize empirical risk. In addition, no parameters need to be tuned in SVMs, barring the upper bound for non-separable cases in linear SVMs. Since SVMs were originally devised for binary classification, however they are not intrinsically geared for multiclass classifications as in credit ratings. Thus, researchers have tried to extend the original SVM to multiclass classification. Hitherto, a variety of techniques to extend standard SVMs to multiclass SVMs (MSVMs) has been proposed in the literature Only a few types of MSVM are, however, tested using prior studies that apply MSVMs to credit ratings studies. In this study, we examined six different techniques of MSVMs: (1) One-Against-One, (2) One-Against-AIL (3) DAGSVM, (4) ECOC, (5) Method of Weston and Watkins, and (6) Method of Crammer and Singer. In addition, we examined the prediction accuracy of some modified version of conventional MSVM techniques. To find the most appropriate technique of MSVMs for corporate bond rating, we applied all the techniques of MSVMs to a real-world case of credit rating in Korea. The best application is in corporate bond rating, which is the most frequently studied area of credit rating for specific debt issues or other financial obligations. For our study the research data were collected from National Information and Credit Evaluation, Inc., a major bond-rating company in Korea. The data set is comprised of the bond-ratings for the year 2002 and various financial variables for 1,295 companies from the manufacturing industry in Korea. We compared the results of these techniques with one another, and with those of traditional methods for credit ratings, such as multiple discriminant analysis (MDA), multinomial logistic regression (MLOGIT), and artificial neural networks (ANNs). As a result, we found that DAGSVM with an ordered list was the best approach for the prediction of bond rating. In addition, we found that the modified version of ECOC approach can yield higher prediction accuracy for the cases showing clear patterns.

폐암 환자의 정위체부방사선치료 시 기준선 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질 및 유용성 평가 (Image quality and usefulness evaluaton of 3D-CBCT and Gated-CBCT according to baseline changes for SBRT of Lung Cancer)

  • 한국희;신충훈;이충환;유순미;박자람;김진수;윤인하
    • 대한방사선치료학회지
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    • 제35권
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    • pp.41-51
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    • 2023
  • 목 적: 본 연구는 폐암 환자의 정위체부방사선치료 시(Stereotactic Body Radiation Therapy, SBRT) 기준선(Baseline) 변화에 따른 3D-CBCT(Cone Beam Computed-Tomography)와 Gated-CBCT의 영상 품질(Image quality)을 비교 분석하여 호흡에 따른 움직임의 보정에 유용한 CBCT 촬영 방법을 찾고자 한다. 대상 및 방법: QUASARTM(Modus Medical Devices Inc, Canada) 팬텀에 지름이 3 cm인 고체 종양 물질(Solid Tumor)을 삽입하여 팬텀의 속도를 주기 3 sec, 최대 진폭 20 mm 로 4DCT(4-Dimentional Computed-Tomography)를 촬영하였다. 전산화 치료계획시스템 EclipseTM을 이용하여 고체 종양 물질에 육안적 종양용적(Gross Target Volume, GTV)을 윤곽 묘사하였다. Truebeam STxTM을 이용해 4DCT 촬영 시와 동일하게 설정한 후, 기준선 변화가 1 mm, 3 mm, 5 mm인 호흡 패턴을 팬텀에 입력하여 3D-CBCT(Spotlight, Full)와 Gated-CBCT(Spotlight, Full) 영상을 5회 반복하여 획득하였다. 획득된 영상을 4DCT 영상을 기준으로 신호대잡음비(Signal-to-Noise Ratio, SNR), 대조대잡음비(Contrast-to-Noise Ratio, CNR), 종양 체적 길이(Tumor Volume Length) 및 모션 블러링 비(Motion Blurring Ratio, MBR)를 측정하여 비교하였다. 결 과: Spotlight Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 13.30±0.10%, 대조대잡음비가 평균 7.78±0.16%, 종양 체적 길이가 평균 3.55 ± 0.17%, 모션 블러링 비가 평균 1.18 ± 0.06%로 Spotlight 3D-CBCT보다 우수한 값을 보였다. 또한, Full Gated-CBCT 영상이 기준선 변화에 따른 신호대잡음비가 평균 12.80 ± 0.11%, 대조대잡음비가 평균 7.60 ± 0.11%, 종양 체적 길이가 평균 3.54 ± 0.16%, 모션 블러링 비가 평균 1.18 ± 0.05%로 Full 3D-CBCT보다 우수한 값을 보였다. 결 론: 3D-CBCT 촬영 영상과 비교하여 Gated-CBCT 촬영 영상이 기준선 변화에 따른 영상 품질이 우수한 값을 보였으며, 호흡으로 인한 모션 블러링 인공물(Motion Blurring Artifacts)의 영향이 적은 것을 확인했다. 따라서 단기간에 고선량을 전달하는 폐암의 정위체부방사선치료 시 불규칙한 호흡으로 인한 기준선 변화가 발생하는 경우 Gated-CBCT를 이용해 영상유도(Image Guide)를 하는 것이 유용하다고 판단된다.

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CNN을 적용한 한국어 상품평 감성분석: 형태소 임베딩을 중심으로 (Sentiment Analysis of Korean Reviews Using CNN: Focusing on Morpheme Embedding)

  • 박현정;송민채;신경식
    • 지능정보연구
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    • 제24권2호
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    • pp.59-83
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    • 2018
  • 고객과 대중의 니즈를 파악하기 위한 감성분석의 중요성이 커지면서 최근 영어 텍스트를 대상으로 다양한 딥러닝 모델들이 소개되고 있다. 본 연구는 영어와 한국어의 언어적인 차이에 주목하여 딥러닝 모델을 한국어 상품평 텍스트의 감성분석에 적용할 때 부딪히게 되는 기본적인 이슈들에 대하여 실증적으로 살펴본다. 즉, 딥러닝 모델의 입력으로 사용되는 단어 벡터(word vector)를 형태소 수준에서 도출하고, 여러 형태소 벡터(morpheme vector) 도출 대안에 따라 감성분석의 정확도가 어떻게 달라지는지를 비정태적(non-static) CNN(Convolutional Neural Network) 모델을 사용하여 검증한다. 형태소 벡터 도출 대안은 CBOW(Continuous Bag-Of-Words)를 기본적으로 적용하고, 입력 데이터의 종류, 문장 분리와 맞춤법 및 띄어쓰기 교정, 품사 선택, 품사 태그 부착, 고려 형태소의 최소 빈도수 등과 같은 기준에 따라 달라진다. 형태소 벡터 도출 시, 문법 준수도가 낮더라도 감성분석 대상과 같은 도메인의 텍스트를 사용하고, 문장 분리 외에 맞춤법 및 띄어쓰기 전처리를 하며, 분석불능 범주를 포함한 모든 품사를 고려할 때 감성분석의 분류 정확도가 향상되는 결과를 얻었다. 동음이의어 비율이 높은 한국어 특성 때문에 고려한 품사 태그 부착 방안과 포함할 형태소에 대한 최소 빈도수 기준은 뚜렷한 영향이 없는 것으로 나타났다.